Simulink Control Design™ - MathWorks

The unit of time is minutes (all plots are in minutes, not seconds).

s = tf('s');

G = [87.8 -86.4 ; 108.2 -109.6]/(75*s+1);

G.InputName = {'L','V'};

G.OutputName = {'yD','yB'};

Control Architecture

The control objectives are as follows:

• Independent control of the tops and bottoms concentrations by ensuring that a change
  in the tops setpoint Dsp has little impact on the bottoms concentration B and vice
  versa


• Response time of about 4 minutes with less than 15% overshoot


• Fast rejection of input disturbances affecting the effective reflux L and boilup V

To achieve these objectives we use the control architecture shown below. This

architecture consists of a static decoupling matrix DM in series with two PI controllers for

the reflux L and boilup V.

open_system('rct_distillation')

12 Loop-Shaping Design